<!DOCTYPE html>

<html>
  <head>
    <meta charset="utf-8">
    
    <title>numpy.nested_iters &mdash; NumPy v1.18 Manual</title>
    
    <link rel="stylesheet" type="text/css" href="../../_static/css/spc-bootstrap.css">
    <link rel="stylesheet" type="text/css" href="../../_static/css/spc-extend.css">
    <link rel="stylesheet" href="../../_static/scipy.css" type="text/css" >
    <link rel="stylesheet" href="../../_static/pygments.css" type="text/css" >
    <link rel="stylesheet" href="../../_static/graphviz.css" type="text/css" >
    
    <script type="text/javascript">
      var DOCUMENTATION_OPTIONS = {
        URL_ROOT:    '../../',
        VERSION:     '1.18.1',
        COLLAPSE_INDEX: false,
        FILE_SUFFIX: '.html',
        HAS_SOURCE:  false
      };
    </script>
    <script type="text/javascript" src="../../_static/jquery.js"></script>
    <script type="text/javascript" src="../../_static/underscore.js"></script>
    <script type="text/javascript" src="../../_static/doctools.js"></script>
    <script type="text/javascript" src="../../_static/language_data.js"></script>
    <script type="text/javascript" src="../../_static/js/copybutton.js"></script>
    <link rel="author" title="About these documents" href="../../about.html" >
    <link rel="index" title="Index" href="../../genindex.html" >
    <link rel="search" title="Search" href="../../search.html" >
    <link rel="top" title="NumPy v1.18 Manual" href="../../index.html" >
    <link rel="up" title="Indexing routines" href="../routines.indexing.html" >
    <link rel="next" title="numpy.flatiter" href="numpy.flatiter.html" >
    <link rel="prev" title="numpy.ndindex.next" href="numpy.ndindex.next.html" > 
  </head>
  <body>
<div class="container">
  <div class="top-scipy-org-logo-header" style="background-color: #a2bae8;">
    <a href="../../index.html">
      <img border=0 alt="NumPy" src="../../_static/numpy_logo.png"></a>
    </div>
  </div>
</div>


    <div class="container">
      <div class="main">
        
	<div class="row-fluid">
	  <div class="span12">
	    <div class="spc-navbar">
              
    <ul class="nav nav-pills pull-left">
        <li class="active"><a href="https://numpy.org/">NumPy.org</a></li>
        <li class="active"><a href="https://numpy.org/doc">Docs</a></li>
        
        <li class="active"><a href="../../index.html">NumPy v1.18 Manual</a></li>
        

          <li class="active"><a href="../index.html" >NumPy Reference</a></li>
          <li class="active"><a href="../routines.html" >Routines</a></li>
          <li class="active"><a href="../routines.indexing.html" accesskey="U">Indexing routines</a></li> 
    </ul>
              
              
    <ul class="nav nav-pills pull-right">
      <li class="active">
        <a href="../../genindex.html" title="General Index"
           accesskey="I">index</a>
      </li>
      <li class="active">
        <a href="numpy.flatiter.html" title="numpy.flatiter"
           accesskey="N">next</a>
      </li>
      <li class="active">
        <a href="numpy.ndindex.next.html" title="numpy.ndindex.next"
           accesskey="P">previous</a>
      </li>
    </ul>
              
	    </div>
	  </div>
	</div>
        

	<div class="row-fluid">
      <div class="spc-rightsidebar span3">
        <div class="sphinxsidebarwrapper">
  <h4>Previous topic</h4>
  <p class="topless"><a href="numpy.ndindex.next.html"
                        title="previous chapter">numpy.ndindex.next</a></p>
  <h4>Next topic</h4>
  <p class="topless"><a href="numpy.flatiter.html"
                        title="next chapter">numpy.flatiter</a></p>
<div id="searchbox" style="display: none" role="search">
  <h4>Quick search</h4>
    <div>
    <form class="search" action="../../search.html" method="get">
      <input type="text" style="width: inherit;" name="q" />
      <input type="submit" value="search" />
      <input type="hidden" name="check_keywords" value="yes" />
      <input type="hidden" name="area" value="default" />
    </form>
    </div>
</div>
<script type="text/javascript">$('#searchbox').show(0);</script>
        </div>
      </div>
          <div class="span9">
            
        <div class="bodywrapper">
          <div class="body" id="spc-section-body">
            
  <div class="section" id="numpy-nested-iters">
<h1>numpy.nested_iters<a class="headerlink" href="#numpy-nested-iters" title="Permalink to this headline">¶</a></h1>
<dl class="function">
<dt id="numpy.nested_iters">
<code class="sig-prename descclassname">numpy.</code><code class="sig-name descname">nested_iters</code><span class="sig-paren">(</span><span class="sig-paren">)</span><a class="headerlink" href="#numpy.nested_iters" title="Permalink to this definition">¶</a></dt>
<dd><p>Create nditers for use in nested loops</p>
<p>Create a tuple of <a class="reference internal" href="numpy.nditer.html#numpy.nditer" title="numpy.nditer"><code class="xref py py-obj docutils literal notranslate"><span class="pre">nditer</span></code></a> objects which iterate in nested loops over
different axes of the op argument. The first iterator is used in the
outermost loop, the last in the innermost loop. Advancing one will change
the subsequent iterators to point at its new element.</p>
<dl class="field-list simple">
<dt class="field-odd">Parameters</dt>
<dd class="field-odd"><dl class="simple">
<dt><strong>op</strong><span class="classifier">ndarray or sequence of array_like</span></dt><dd><p>The array(s) to iterate over.</p>
</dd>
<dt><strong>axes</strong><span class="classifier">list of list of int</span></dt><dd><p>Each item is used as an “op_axes” argument to an nditer</p>
</dd>
<dt><strong>flags, op_flags, op_dtypes, order, casting, buffersize (optional)</strong></dt><dd><p>See <a class="reference internal" href="numpy.nditer.html#numpy.nditer" title="numpy.nditer"><code class="xref py py-obj docutils literal notranslate"><span class="pre">nditer</span></code></a> parameters of the same name</p>
</dd>
</dl>
</dd>
<dt class="field-even">Returns</dt>
<dd class="field-even"><dl class="simple">
<dt><strong>iters</strong><span class="classifier">tuple of nditer</span></dt><dd><p>An nditer for each item in <em class="xref py py-obj">axes</em>, outermost first</p>
</dd>
</dl>
</dd>
</dl>
<div class="admonition seealso">
<p class="admonition-title">See also</p>
<p><a class="reference internal" href="numpy.nditer.html#numpy.nditer" title="numpy.nditer"><code class="xref py py-obj docutils literal notranslate"><span class="pre">nditer</span></code></a></p>
</div>
<p class="rubric">Examples</p>
<p>Basic usage. Note how y is the “flattened” version of
[a[:, 0, :], a[:, 1, 0], a[:, 2, :]] since we specified
the first iter’s axes as [1]</p>
<div class="doctest highlight-default notranslate"><div class="highlight"><pre><span></span><span class="gp">&gt;&gt;&gt; </span><span class="n">a</span> <span class="o">=</span> <span class="n">np</span><span class="o">.</span><span class="n">arange</span><span class="p">(</span><span class="mi">12</span><span class="p">)</span><span class="o">.</span><span class="n">reshape</span><span class="p">(</span><span class="mi">2</span><span class="p">,</span> <span class="mi">3</span><span class="p">,</span> <span class="mi">2</span><span class="p">)</span>
<span class="gp">&gt;&gt;&gt; </span><span class="n">i</span><span class="p">,</span> <span class="n">j</span> <span class="o">=</span> <span class="n">np</span><span class="o">.</span><span class="n">nested_iters</span><span class="p">(</span><span class="n">a</span><span class="p">,</span> <span class="p">[[</span><span class="mi">1</span><span class="p">],</span> <span class="p">[</span><span class="mi">0</span><span class="p">,</span> <span class="mi">2</span><span class="p">]],</span> <span class="n">flags</span><span class="o">=</span><span class="p">[</span><span class="s2">&quot;multi_index&quot;</span><span class="p">])</span>
<span class="gp">&gt;&gt;&gt; </span><span class="k">for</span> <span class="n">x</span> <span class="ow">in</span> <span class="n">i</span><span class="p">:</span>
<span class="gp">... </span>     <span class="nb">print</span><span class="p">(</span><span class="n">i</span><span class="o">.</span><span class="n">multi_index</span><span class="p">)</span>
<span class="gp">... </span>     <span class="k">for</span> <span class="n">y</span> <span class="ow">in</span> <span class="n">j</span><span class="p">:</span>
<span class="gp">... </span>         <span class="nb">print</span><span class="p">(</span><span class="s1">&#39;&#39;</span><span class="p">,</span> <span class="n">j</span><span class="o">.</span><span class="n">multi_index</span><span class="p">,</span> <span class="n">y</span><span class="p">)</span>
<span class="go">(0,)</span>
<span class="go"> (0, 0) 0</span>
<span class="go"> (0, 1) 1</span>
<span class="go"> (1, 0) 6</span>
<span class="go"> (1, 1) 7</span>
<span class="go">(1,)</span>
<span class="go"> (0, 0) 2</span>
<span class="go"> (0, 1) 3</span>
<span class="go"> (1, 0) 8</span>
<span class="go"> (1, 1) 9</span>
<span class="go">(2,)</span>
<span class="go"> (0, 0) 4</span>
<span class="go"> (0, 1) 5</span>
<span class="go"> (1, 0) 10</span>
<span class="go"> (1, 1) 11</span>
</pre></div>
</div>
</dd></dl>

</div>


          </div>
        </div>
          </div>
        </div>
      </div>
    </div>

    <div class="container container-navbar-bottom">
      <div class="spc-navbar">
        
      </div>
    </div>
    <div class="container">
    <div class="footer">
    <div class="row-fluid">
    <ul class="inline pull-left">
      <li>
        &copy; Copyright 2008-2019, The SciPy community.
      </li>
      <li>
      Last updated on Feb 20, 2020.
      </li>
      <li>
      Created using <a href="http://sphinx.pocoo.org/">Sphinx</a> 2.4.2.
      </li>
    </ul>
    </div>
    </div>
    </div>
  </body>
</html>